I am currently the proud owner of some FE207e based MLTLs that I am using with my lovely nuuk built propod system (monica2 + active preamp with 25k attenuator + charlize all with SMPS) and it sounds great.

However:

I am also the owner of a pair of Audio Nirvana Super 8s that I want to use for something and the project that appeals is to add some cheaper drivers with similar efficiency to fill in the base, wire them in parallel with no crossover in an MLTL type enclosure.

I was wondering what sort of dimensions I should use for the enclosure and stuffing and what sort of driver I could add to supplement the bass frequencies? For budget purposes I was thinking of the Eminence Alpha10.

Using MJKs alignment tables, the rules of thumb on Mr Brines'site and the sketchy maths on TL's site and an urgent need to put these dirvers into something, I am preparing to build the following:

AN8Super + Eminence Alpha10 in DDDLLQD using an MLTL tuned to 44.25Hz (6.75Hz above the AN8 and 6.75 Hz below the Emi Alpha) with 90litres of capacity and SL/S0 of 0.1. AN8 over the Emi with the two drivers wired in parallel. I will be driving them with a Super-t unmodified. Source is just lossless digital via a cheapish 24/96 crystal/burr-brown DAC.